Academia Motif
One of the subtle motifs that weaves its way through the novel is academia. The entire novel takes place at Oxford University, at the fictional Shrewsbury College, and the scenery is described in great detail. The key characters are all academics, either professors, or students. There is also an element amongst the characters of judging others by their academic accomplishments; Wimsey, in particular, is an intellectual snob and is very scathing about those who are not blessed with such a quick wit as he is himself.
The events of the novel also remind Harriet that she really did enjoy her time at the university, and that she does not so much enjoy academics as seek refuge there. By submerging herself in her research, and in the atmosphere of learning, she is able to hide from the world.
Town and Gown Symbol
The term "town and gown" is specific to Oxford and Cambridge Universities and is a symbol of the divide in the city between those who are connected to the university and those who are not. The "town" symbolizes people who have regular jobs, do not have the time to indulge in academic pursuits, and who have a life that is totally unconnected from the colleges that make up the bulk of the city. The "gown" symbolizes the college community, both administrators, faculty and students. There is a divide between the two and never the twain shall meet.
Oxford University Symbol
To Harriet, Oxford University in general, and Shrewsbury College in particular, has become a symbol of the most unpleasant and difficult time in her life when she was wrongfully accused of murder and actually had to go to trial accused as such. This symbol is especially strong in the weeks leading up to the Gaudy Dinner. She wants very much to attend but the college reminds her too much of the horrible experience she has been through there, and also symbolizes the way in which she felt ostracized by the community that she had previously believed would support her.
The Gaudy Dinner
The Gaudy Dinner is an allegory for the brevity of life, and the celebration of life that took place when the college was in its infancy, and its young people would gather and bemoan how their youth was fleeting and life in general flew by too fast, and was too short. Although these were no longer subjects that were given much attention at what had become a traditional gala style event, the dinner allegorizes the early days of the institution and the students that blazed the way for those who followed.
Poison Pen Letter Symbol
The phrase "poison pen" symbolizes the cowardice of the person writing and sending it, because it is written anonymously. A poison pen letter is intended to be damaging to the recipient, but also extremely threatening because it generally contains either veiled references to a transgression that they believed to have been private, or outright threats against the person. A poison pen letter is also symbolic of the nastiness of the contents of the missive. The words in the letter are so damaging that they act as a poison and cause great damage.